Asbestos has long been used in cement structures. Problems encountered by use of asbestos have prompted efforts to find replacements. Staple synthetic fibers have been used as reinforcement with pulps as filter aids. Cellulose pulps have been used for this purpose and for reinforcement but cement matrix composites reinforced solely by cellulose have durability problems. Polyolefin pulps which have also been used are relatively inexpensive, however, it is generally known that polyolefin pulps do not function as reinforcing fibers (see Kirk-Othmer: Encyclopedia of Chemical Technology, Volume 19, Third Edition p. 433). Preparation of a cement composite of good flexural toughness by use of a polyethylene pulp is a worthwhile objective.